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作为英国的首都、欧洲的大城市、世界顶级的国际大都市,伦敦的另一个称谓同样为人们熟知——雾都。20世纪初,由于当时人们普遍使用煤作为燃料,产生了大量烟雾。烟雾遇到伦敦的海洋性气候,造成了“远近驰名”的烟霞,伦敦由此得名“雾都”。1952年12月4日,伦敦的特殊天气导致了呛人的浓厚烟雾弥漫全城5天之久,几天内死亡人数比平时增加了4000人,这就是著名的“伦敦大雾”事件。1956年开始,英国政府连续针对空气治理颁布了多项法令。1975年,伦敦的烟雾天由每年几十天减少到了15天。但是,故事并没有就此完结。从20世纪80年代开始,数量持续增加的汽车取代煤成为大气的主要污染源。汽车排放的氮氧化物、一氧化碳、不稳定有机化合物在阳光中的紫外线作用下发生复杂的光化学反应,产。生了以臭氧为主的“光化学烟雾”。
As the capital of Britain, the European metropolis, the world’s top international metropolis, London, another title is also well known - the fog. At the beginning of the 20th century, due to the widespread use of coal as a fuel at that time, a large amount of smoke was generated. Smoke met London’s maritime climate, resulting in “far and near famous ” haze, London hence the name “fog ”. December 4, 1952, London’s special weather led to choking thick smoke filled the city for 5 days, the death toll increased by 4,000 over usual, which is known as the “London fog” incident . Beginning in 1956, the British government issued a number of ordinances on air pollution control. In 1975, the days of smog in London were reduced from dozens of days a year to 15 days. However, the story did not end there. Since the 1980s, the increasing number of cars replacing coal has become the major source of air pollution. Car emissions of nitrogen oxides, carbon monoxide, unstable organic compounds in the sunlight under the action of ultraviolet light complex photochemical reactions. Born ozone-based “Photochemical smog ”.